From German patent publication No. 2,900,728 and the corresponding U.S. Pat. No. 4,479,220 a dye laser is known, which makes use of distributed feedback to produce ultrashort laser pulses. The distributed feedback laser described therein, which employs an optical grating as a beam divider, has a distinct advantage over earlier designs with a conventional beam splitter, in that the dye-laser wavelength produced is no longer dependent upon the pump laser wavelength. However, the fact that the location of the plane in which the interference pattern for producing the distributed feedback is formed is wavelength-dependent, has proved to be a practical disadvantage. This disadvantage is overcome by an arrangement proposed by another German patent application No. P 3,633,469.3 (U.S. application, Ser. No. 101,962 filed September 28, 1987, now abandoned). By use of a second grating, both the period and the spatial position of the interference pattern are rendered fully independent of the pump radiation wavelength. Disadvantages of this arrangement, however, are the necessity of a second grating, which increases the required expense of both material and time for adjusting the arrangement, and a critically diminished degree of effectiveness for the entire arrangement due to the double diffraction and the associated high loss of light.